MEDIUMCVSS v4 5.3Vulnerability
CVE-2026-66912
Zimbra is vulnerable to Stored Cross-Site Scripting (XSS) via the From email header during HTML reply composition in Classic UI. Due to insufficient sanitization of the From header value, a remote attacker can send a crafted email containing a malicious From header with an embedded JavaScript payload. When the victim opens the message in Classic UI and clicks Reply while composing in HTML mode with reply headers disabled, the unsanitized From header content is rendered as HTML and the JavaScript payload executes in the victim's browser, potentially allowing the attacker to steal session information or perform actions on behalf of the victim. This issue was fixed in version 10.1.21
Properties
- Cvss score
- 5.3
- First seen
- 2026-10-29T18:31:06+00:00
- Last seen
- 2026-10-29T18:31:06+00:00
- Euvd assigner
- CERT-PL
- Retrieved at
- 2026-10-29T19:54:43+00:00
- Src batch id
- euvd-20261029T193401Z-a7e82d
- Source url
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-112942
- Score
- 5.3
- Euvd base score version
- 4.0
- Fetched at
- 2026-10-29T19:34:21+00:00
- Euvd vendor
- Synacor
- Cvss vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- First seen by Signal
- 2026-10-29T19:34:21+00:00
- Euvd base score
- 5.3
- Vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Content hash
- 97da11fc4be7fc4541259422e44cf4d443ac37502481ac39aa542e4f3ed0a4d7
- Published at
- 2026-10-29T16:18:15.530
- Last modified
- 2026-10-29T16:29:56.553
- Euvd updated
- 2026-10-29T18:31:06+00:00
- Euvd epss pct
- 0
Related Entities (1)
HAS_WEAKNESS (1)
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